Active matrix substrate, method for fabricating active matrix substrate, display device, liquid crystal display device, and television device

Abstract

An active matrix substrate includes a substrate, a TFT formed on the substrate, a storage capacitor element formed on the substrate, an interlayer insulating film covering the storage capacitor element, and a pixel electrode formed on the interlayer insulating film. The storage capacitor element includes a storage capacitor line, an insulating film formed on the storage capacitor line, and two or more storage capacitor electrodes opposed to the storage capacitor line with the insulating film interposed therebetween. The two or more storage capacitor electrodes are electrically connected via associated contact holes formed in the interlayer insulating film to the pixel electrode and electrically continuous with a drain electrode of the TFT.

1. An active matrix substrate comprising:
 a substrate; an active element formed on the substrate; a storage capacitor element formed on the substrate; an interlayer insulating film covering the storage capacitor element; and a pixel electrode formed on the interlayer insulating film, 
 wherein the storage capacitor element includes a storage capacitor line, an insulating film formed on the storage capacitor line, and two storage capacitor electrodes opposed to the storage capacitor line with the insulating film interposed between the storage capacitor electrodes and the storage capacitor line, 
 the two storage capacitor electrodes are electrically connected via associated contact holes formed in the interlayer insulating film to the pixel electrode and electrically continuous with a drain electrode of the active element, and 
 wherein areas of the two storage capacitor electrodes are different from each other. 
 
     
     
       2. The active matrix substrate of  claim 1 , wherein at least one of the two storage capacitor electrodes is connected to a connection electrode connected to the drain electrode. 
     
     
       3. The active matrix substrate of  claim 2 , wherein the two storage capacitor electrodes include a storage capacitor electrode connected to the connection electrode and a storage capacitor electrode prevented from being connected to the connection electrode, and the area of a region of the storage capacitor line on which the storage capacitor electrode connected to the connection electrode is placed is different from that of a region of the storage capacitor line on which the storage capacitor electrode prevented from being connected to the connection electrode is placed. 
     
     
       4. The active matrix substrate of  claim 1 , wherein a slit is formed in the storage capacitor line so as to be located between each adjacent pair of the storage capacitor electrodes. 
     
     
       5. The active matrix substrate of  claim 4 , wherein a slit is formed in the interlayer insulating film to overlap the slit of the storage capacitor line. 
     
     
       6. The active matrix substrate of  claim 4 , wherein the slit of the storage capacitor line has a width of 5 μm or more. 
     
     
       7. The active matrix substrate of  claim 4 , wherein
 the active element includes first and second active elements, 
 the pixel electrode includes first and second pixel electrodes adjacent to each other, 
 the two or more storage capacitor electrodes include first and second storage capacitor electrodes, 
 the first storage capacitor electrode is connected to the first pixel electrode and a drain electrode of the first active element while the second storage capacitor electrode is connected to the second pixel electrode and a drain electrode of the second active element, and 
 a first data signal is fed through the first active element to the first pixel electrode while a second data signal different from the first data signal is fed through the second active element to the second pixel electrode. 
 
     
     
       8. The active matrix substrate of  claim 7 , wherein the slit of the storage capacitor line coincides with part of the first pixel electrode or part of the second pixel electrode. 
     
     
       9. A display device comprising: the active matrix substrate of  claim 1 ; a counter electrode opposed to the active matrix substrate; and a display medium layer placed in the gap between the active matrix substrate and the counter electrode,
 wherein the same electrical potential is applied to the storage capacitor line and the counter electrode. 
 
     
     
       10. A television device comprising the display device of  claim 9 . 
     
     
       11. A liquid crystal display device comprising: the active matrix substrate of  claim 1 ; a counter substrate whose one surface is formed with a counter electrode opposed to the active matrix substrate; and a liquid crystal layer placed in the gap between the active matrix substrate and the counter substrate. 
     
     
       12. The liquid crystal display device of  claim 11 , wherein the same electrical potential is applied to the storage capacitor line and the counter electrode. 
     
     
       13. The liquid crystal display device of  claim 12 , wherein the liquid crystal layer is a vertical alignment type liquid crystal layer containing nematic liquid crystal material having a negative dielectric anisotropy. 
     
     
       14. The liquid crystal display device of  claim 13  driven in a normally black mode. 
     
     
       15. The liquid crystal display device of  claim 11 , wherein different electrical potentials are applied to the storage capacitor line and the counter electrode. 
     
     
       16. The liquid crystal display device of  claim 15 , wherein the liquid crystal layer is a twist-aligned liquid crystal layer containing nematic liquid crystal material having a positive dielectric anisotropy. 
     
     
       17. The liquid crystal display device of  claim 16  driven in a normally white mode. 
     
     
       18. The liquid crystal display device of  claim 11 , wherein the storage capacitor line has a slit between each adjacent pair of the storage capacitor electrodes, and
 the counter substrate is provided with a black matrix overlapping the slit. 
 
     
     
       19. A television device comprising the liquid crystal display device of  claim 11 .